I table a motion!

So just when you thought I wooden make any more puns...

...I decided to make a coffee table. Not just any old coffee table though, oh no... I'm opting for an awesome one! One SOOOO ludicrous, the actual chances of me completing it are about the same as... well something utterly ridiculous; like me being able to pull an even number of socks out of the washing machine... or stopping the microwave at the exact time that the handle of the mug I put in is actually facing me. You know, crazy stuff that just won't happen in my lifetime, that kinda thing.

Steampunk is cool. So I started off with a steampunk theme, and that of course means travel, navigation, astronomy, brass, wood, leather, glass, etc.

I had a look around and found a beautiful and inspirational image of a sextant, which I thought would suit this perfectly. It's all metal, but should look great in wood.

The top flips back on a hinge to reveal the inner workings. Now wouldn't that be great in wood?

Beautiful, eh? So I decided to take this as the inspiration; the table legs would be the screws, the top of the table should hinge back and reveal the inner area, etc. To start with I mocked it up in ZBrush and did a few quick renders with Keyshot.

It was looking promising and the idea seemed to be solid, it's just a matter of working out some of the design ideas a bit better... I wasn't happy with the top of it, so decided to have alook around to see what else I could do there rather than the original sextant idea. This had to be a working table, so having a piece protruding from the top wasn't going to work. I also wasn't thrilled with the inner piece... In keeping with the astronomical theme, I searched for an orrery and accidentally came across a thing called an astrolabe. It was a mechanical device used in antiquity and is an elaborate inclinometer, historically used by astronomers and navigators, to measure the inclined position in the sky of a celestial body, day or night. It can thus be used to identify stars or planets, to determine local latitude given local time and vice versa, to survey, or to triangulate (guess who just visited wikipedia *cough*).

So in searching for more info about this device, I came across the rather excellent website http://www.astrolabeproject.com/

Some generous souls there allow you to print out vector graphic versions of the astrolabe, specific to your region. Perfect! So I entered the values for Dublin, Ireland, and hey presto, a free astrolabe, supplied as a vector graphic, perfect for printing out and CNC'ing. Doesn't get much luckier than this, didn't fancy making this in Photoshop or Illustrator (mostly coz I can't use Illustrator).

The settings used for Dublin, Ireland

The scale of my original model also seemed to work until I actually printed the top part out to scale and spread it out on the ground. At almost a metre in diameter, it was FAR too wide. I scaled it down to 800mm instead and it seemed about right for a coffee table. Back to ZBrush to update the model.

So this was closer to the actual dimensions I would need. I opted for European oak as the wood of choice on the advice of the master craftsman Chaïm from Hillpicket Studio, here in Avoca, Co. Wicklow. This guy is great, and is basically teaching me how to build this whole table. It's a bit of a drive away (86km or so), but totally worth it, as relying on his experience is the only way I'm going to get this made. Go take a course there now. 


You heard me. Nicest guy you'll ever meet, you won't regret it!

Anyway, I've decided to distress this to make it look like the kind of thing you'd find on the back of the Black Pearl from Pirates of the Caribbean, so it will ultimately be more aged looking than it is here. Also, some of the grain goes the wrong way, etc, but this render is purely for scale and dimensions really so I'm just gonna keep it as is.

Looking at it though, it still needs work. The astrolabe has nowhere to sit and it's looking a bit boring.
It looks like this (see below) and is going to need to be seen in order to be used properly. It also has a moving part called a rete (pronounced ree-tee), shown below in thick black, and this should spin on the central axis and depending on the angle chosen, will point to various stars (the pointy bits). So yeah, this has now become an engineering challenge... (gulp!)

So anyway, back to ZBrush for more changes if this design is gonna make it on top.

Entire table with glass on top and I decided to add a small door for storage. The hand crank is intended to spin the rete.

The top temporarily hidden, to show the inner mechanics on a shelf inside.

Hidden top showing the crank and worm gear mechanism necessary to spin the rete.

Here I've hidden the main barrel and the top and even legs to show the proposed worm gear and crank to drive the rete.

So as you can see, I've clearly gone mad. This thing is gonna to take forever to build...

I'm also intending on burning in some designs on the side, either on the door itself or the other side with something like this, coz why not add pyrography to the mix, right? ...right...? *takes out credit card and orders a pyrography machine*

So, the design isn't actually finished yet, but it's at a stage where the woodworking of certain parts can certainly take place. In actual fact, I started on the hinge some time ago and it's still valid, so that just proves my point. Just sayin' is all....

Here's the progress so far.
The beginnings of an oak hinge

The secondings of an oak hinge

The gluing of an oak hinge

The finaling of an oak hinge

The backings of an oak hinge (see what I did there? All these "ings" just for that one - totally worth it)

The hinging of an oak hinge.... I mean, a working hinge! Complete with automatic stopper built in. Pleased with this.

I also cut out a quick small latch to go on the door also (quite frankly there are so many parts to this table, I just need to make progress wherever I can).
A latch for the door. I'm probably going to change the rete pointers to match this motif, although the pointers will probably end up brass.

I also turned some wooden screw heads which are going to be glued onto the hinge to simulate the real thing. Not thrilled with how these came out, they don't hold up great to close inspection, so may have to revisit these. Haven't glued them on just yet.
Some screwed up screws...

Okay, so the next stage was to make the base. The wood planks come 24mm thick, so although the original design was thicker than that, on Chaïm's advice I'm compromising in order to save on weight, hassle and time. I'm just gonna go with the 24mm and see what kind of router cutter will give me a nice profile.

The main base circle is divided up into 4 parts. The hole in the middle will accommodate a plywood base which should be lighter than the oak (this table is already going to get incredibly heavy). The important thing is that each of the 4 parts have the grain of the wood go along their length for maximum strength. To do this, two planks are glued together for each of these parts and then a template is made out of plywood in order to cut them all consistently the same size. As the base is 800mm in diameter and the hole is 600mm, I measured up the inner and outer diameters, drew the outline on a piece of plywood, and then traced this template on the planks, ensuring to keep the wood grain as long as possible. The pieces were then cut on the large bandsaw (thank you Chaïm) and then came the business of sanding them down. After some planing on the edges I realised I was never gonna get them to line up perfectly, so we went back to the sander and that did a great job of straightening them out. Next stage is to draw up some dowel marks, drill some holes for the dowels and then glue them into one piece.

4 pieces, grain running as long as possible, ready for dowel marking and gluing

An early look at hinge size on the base.
Dowels added to increase surface gluing area and prevent slippage
All glued and strapped together. You could call this a strapping piece of work... (you'd be awful if you did, but still, the option's there)

I'm also in the process of trying to figure out the top part of the table. I've been thinking about how to make it so the lid can lift and pass the central pillar which is driving the rete. So I've come up with this solution for now.

A centre piece "cog" should allow the top to hinge upwards without catching the rete. It will also allow the rete to grip the centre piece and rotate.

Just a round hole needed for the main table top (rete hidden for clarity). Clearance when pivoting the table open shouldn't be an issue.

Should be able to make this in 2 pieces and glue them together. Right now there's a good chance I'll have to get a metal gear worm (rather than make one from wood) and attach this new cog to that.

As ever - wildly ambitious!

Chaïm has advised I get some flexi plywood for the main barrel, which I've ordered today. The grain should be vertical in order to not split as it bends. As the main barrel is 400mm in diameter, and as C = πd, the circumference works out to be 1256mm, and these sheets come in 1220 x 2400. Just 36mm short of using the bottom half of a sheet rather than having to cut into the 2400 length. Had the circumference been 380mm wide, I could have saved a lot on plywood. Lesson learned. Ah well!